Labeled bile acids V: Deuterium and carbon‐13 labeled cholic, chenodeoxycholic and ursodeoxycholic acids

Abstract

This paper describes a general, simple and short procedure for the introduction o f stable isotopes (deuterium and carbon-13) to the side chain of bile acids. The bisnorcholyl aldehydes of cholic and chenodeoxycholic acids are key intermediates, while the isotope is introduced by the Wittig condensation o f [1 ,2-13 C2]-(carbethoxyrnethylene)triphenylphosphorane.

Chemical synthesis of (22E)-3α,6β,7β-trihydroxy-5β-chol-22-en-24-oic acid and its taurine and glycine conjugates

“…The one-step dihydroxylation is much more simple and straightforward than the two-step procedure reported by Kihira and Hoshita (13) and Kihira and others (20,21), in which epoxidation of the 22-ene and its methyl ester, the stereochemical configuration of the ⌬ 22 -double bond as an E-form was determined on the basis of a large coupling constant ( J, 15-16 Hz) arising from a doublet signal of the 23-H in the 1 H-NMR (13,22) and of characteristic olefinic carbon signal pairs appearing at ‫911ف‬ and 155 ppm, respectively assigned to C-23 and C-22, in the 13 C-NMR (4,11).…”

“…Because the free sulfonic acid form of tauro-⌬ 22 -␤-MCA [1b] is highly hygroscopic, it was converted to the sodium salt by treatment with NaOH and then purified and isolated as a crystalline product by passing through a prepacked Sep-Pac Vac tC 18 cartridge for reversed-phase solid extraction, eluting with 50% aqueous methanol. On the other hand, the glycine methyl ester form of glyco-⌬ 22 Figure 3 shows ESI-NIM mass spectra of unconjugated ⌬ 22 -␤-MCA acid and its taurine and glycine conjugates (Fig. 3A-C).…”

“…The last fraction, which contains the desired component, was evaporated under reduced pressure, and the residue was recrystallized from methanol-ether to give the taurine-conjugated ⌬ 22 …”

Preparation of Carbon‐14‐Labeled Compounds via Multi‐Carbon Building Blocks of the [ 14 C]Carbon Dioxide Tree

“…An example is the side-chain construction leading to 24-methylidene[24-14 C]cholesterol (165) for use in biosynthetic studies (Figure 6.51). Similar chemistry was used to prepare carbon-13-labeled bile acids 103 . Intermediate steps to hydrolyze the ester group and reduce the a,b-double bond, as well as to modify the A/B ring functionality, produced 163.…”

Synthesis and characterization of organometallic rhenium(І) and technetium(І) bile acid complexes

“…ECT (emission computed tomography) is a technology making use of the radioactivity nuclide to diagnose. The former radiopharmaceuticals for hepatobiliary scintigraphy have mainly 99m Tc-IDA, 99m Tc-IDA derivatives, 99m Tc-GH and 99m Tc-PMT [4][5][6]. Although these radiopharmaceuticals have exerted important role, some hepatobiliary diseases, liver tumor and intestinal cancer are still not diagnosed accurately because of the limitation of specificity and affinity of these radiopharmaceuticals to cancer cell.…”